Complex Coronary Artery Lesions Research Articles

Safety and efficacy of multiple, overlapping polymer-based paclitaxel-eluting stents

To provide insight on the patients with long lesions that received multiple, overlapping stents by reporting clinical outcomes, together with a detailed angiographic and intravascular ultrasound analysis of the overlap zone. TAXUS VI is a prospective, multicentre, double-blind, trial, specifically designed to assess outcomes of paclitaxel-eluting stents in longer lesions by randomising 446 patients (1:1) between a drug-eluting TAXUS Express2 Moderate Release (MR) and an uncoated Express2 control stent. Multiple overlapping stents were implanted in 124 patients (27.8%) and are the subject of this report. Clinical, angiographic and IVUS outcomes at nine months were compared in the overlap group for patients receiving the TAXUS Express2 MR stent and the uncoated Express2 stent. In the overlap group, mean lesion length was 25.1 mm with a mean stent length of 43.6 mm. At nine months, TVR was reduced by 94% from 25.0% to 1.6% in the TAXUS patients compared with control (p=<0.0001); TLR was reduced by 93% from 23.3% to 1.6% (p=0.0002). Binary restenosis in the stented area was reduced by 89% from 45.5% in the control patients to 4.8% in the TAXUS patients (p<0.0001). There was a trend towards a higher 30-day myocardial infarction rate in the TAXUS group (7.9% vs. 1.6%; p=0.21), but by nine months, MACE was significantly reduced by 62.0%, from 25.0% to 9.5% in favour of the TAXUS patients (p=0.0305). Late acquired incomplete apposition on IVUS was infrequent in either group and was not located in the overlap zone, nor was the finding associated with late MACE. No stent thrombosis occurred in either group. The use of multiple overlapping TAXUS MR stents appears safe and effective in the treatment of long complex coronary artery lesions.

Utility of multislice computed tomography as a strategic tool for complex percutaneous coronary intervention

Multislice computed tomography (MSCT) has been currently utilized as a non-invasive diagnostic modality to detect coronary artery disease. We sought to investigate whether preprocedural lesion assessment by MSCT could offer strategic guidance in the setting of elective complex percutaneous coronary intervention (PCI). Twenty-six complex coronary artery lesions in 23 patients were evaluated using 16-row MSCT scanner and an off-line image analysis workstation prior to the PCI. Procedural strategies of PCI were planned based on the morphologic and geometric analysis of the target lesion and vessel. MSCT provided valuable strategic information, which was useful for subsequent PCI procedure. The three-dimensional computed tomography (CT) images allowed us to determine optimal working view angle that best demonstrated the target lesion with least foreshortening. Furthermore, the thin-slab maximum intensity projected CT images of the target lesion served as a preprocedural road map depicting the bends of complex luminal path, vessel geometry and occluded segment of the vessel. As results, procedural success was achieved in all cases with complex lesions including chronic total occlusion. Our preliminary results showed that preprocedural lesion and vessel assessment by MSCT provided important additive strategic information that led to successful complex PCI procedures.

Final results from the multi-center trial of the angiosculpt scoring balloon catheter for the treatment of complex coronary artery lesions

Final results from the multi-center trial of the angiosculpt scoring balloon catheter for the treatment of complex coronary artery lesions

Initial Experience With a Magnetic Navigation System for Percutaneous Coronary Intervention in Complex Coronary Artery Lesions

The aim of this study was to evaluate the feasibility of a magnetic-assisted navigation system during percutaneous coronary intervention (PCI) of tortuous and severely angulated coronary arteries. The magnetic navigation system consists of two 0.8-T permanent magnets which generate a magnetic field over the heart. Altering the magnetic vector deflects a coronary guidewire with a magnetic tip. Patients were selected for magnetic-assisted intervention (MAI) for potentially difficult to cross lesions. The time required for placement of the guidewire, total procedure time, fluoroscopy time, and amount of contrast for the procedure were recorded. There were a total of 59 patients undergoing PCI of 68 lesions. Patients were grouped based on whether MAI was attempted as a first option ("primary attempt"; n = 46) or following failure to pass a conventional guidewire ("secondary attempt"; n = 13). The target lesion was successfully crossed in 49 of 55 lesions (89%) and 9 of 13 lesions (69%) in patients undergoing primary and secondary attempts, respectively. The procedural success rates were 84% and 62%, respectively. Most lesions were located in the circumflex artery territory (39% and 62% of lesions, respectively). The median (25th and 75th percentiles) time for crossing the lesion was longer in the secondary attempt group (14.8 [5, 15.5] vs. 28.9 [8, 38] min). Median fluoroscopy time and median contrast used were also higher among the secondary attempt group. This first report of MAI suggests that it may become a useful adjunct for wire placement in difficult coronary interventions.

The Stenting Coronary Arteries in Non-stress/benestent Disease (SCANDSTENT) Trial

The purpose of the SCANDSTENT study was to evaluate the use of sirolimus-eluting stents (SES) in complex coronary lesions. The use of SES improves angiographic and clinical outcomes compared with bare-metal stents (BMS) in simple coronary artery lesions, but there is limited evidence of their safety and efficacy when implanted in complex lesions. We randomly assigned 322 patients with symptomatic complex coronary artery disease to receive either SES or BMS. The lesions were occluded (36%), bifurcational (34%), ostial (22%), or angulated (8%) in morphology. The primary end point was the difference in minimal lumen diameter six months after stent implantation. The patients were well matched in terms of demographic and angiographic baseline characteristics; 18% had diabetes. The reference vessel diameter was 2.86 mm in mean, and the lesion length 18.0 mm. At follow-up, patients who received SES had a minimal lumen diameter of 2.48 mm compared with 1.65 mm in those who received BMS (p < 0.001), a diameter stenosis of 19.3% versus 43.8% (p < 0.001), and 2.0% versus 31.9% developed restenosis (p < 0.001). The rate of major adverse cardiac events was 4.3% with SES versus 29.3% with BMS (p < 0.001), and stent thrombosis was observed in 0.6% in the SES group versus 3.1% in the BMS group (p = 0.15). The use of SES markedly reduced restenosis and the occurrence of major adverse cardiac events in patients with complex coronary artery lesions without increasing the risk of stent thrombosis.

Clinical Efficacy of Polymer-Based Paclitaxel-Eluting Stents in the Treatment of Complex, Long Coronary Artery Lesions From a Multicenter, Randomized Trial

Intracoronary polymer-based stent delivery of paclitaxel has been shown to be effective in reducing restenosis in simple coronary lesions, but the evidence base for contemporary use in longer, more complex coronary stenoses is lacking. TAXUS VI is a prospective, multicenter, double-blind, randomized trial assessing clinical and angiographic outcomes of the TAXUS Moderate Release paclitaxel-eluting stent in the treatment of long, complex coronary artery lesions. Four hundred forty-eight patients at 44 sites were randomized (1:1) between a drug-eluting TAXUS Express2 and an uncoated Express2 control stent. Per protocol, the 9-month follow-up included an angiographic reevaluation in all patients. The primary end point was the rate of target-vessel revascularization 9 months after the study procedure; secondary end points included the rate of target-lesion revascularization and binary restenosis at follow-up. Mean lesion length in the study was 20.6 mm, with a mean stent-covered length of 33.4 mm. Of all lesions, 55.6% were classified as complex lesions (type C of the AHA/ACC classification). At 9 months, target-vessel revascularization was 9.1% in the TAXUS group and 19.4% in the control group (P=0.0027; relative reduction, 53%). Target-lesion revascularization was reduced from 18.9% to 6.8%, respectively (P=0.0001). The incidence of major adverse cardiac events was similar in the 2 groups, 16.4% and 22.5% in TAXUS and control, respectively (P=0.12), including comparable rates for acute myocardial infarction. Binary restenosis in the stented area was reduced from 32.9% in the control group to 9.1% in the TAXUS patients (P<0.0001). The finding that the TAXUS Moderate Release stent system is safe and effective in the treatment of long, complex coronary artery lesions provides the evidence base for the more widespread use of drug-eluting stents in contemporary clinical practice.

Sirolimus-eluting coronary stents: novel devices for the management of coronary artery disease.

Despite major technological advances in the practice of percutaneous coronary intervention, restenosis of the treated arteries remains a challenge for many interventional cardiologists. Sirolimus is a macrolide antibiotic with potent antifungal, immunosuppressive, and antimitotic activities. Sirolimus inhibits in-stent restenosis via 2 major mechanisms of action: by blocking the process of neointimal hyperplasia by inhibiting smooth muscle cell proliferation and by inhibiting inflammatory cell activity. In pivotal clinical trials, the sirolimus-eluting stent has demonstrated significant improvements in angiographic and clinical outcomes compared with bare metal stents in patients with de novo lesions in native coronary arteries. Since the systemic exposure of sirolimus in patients who received the drug-eluting stent is minimal, adverse effects resulting from systemic exposure of sirolimus are unlikely to occur. Further studies are needed to determine the safety and effectiveness of sirolimus-eluting stents in patients with more complex coronary artery lesions. In addition, the long-term safety, efficacy, and cost-effectiveness of this novel drug-eluting device will need to be established in ongoing clinical trials. This review article focuses on the pharmacology as well as clinical studies of the sirolimus-eluting stent.

P1-17 Effects of intracoronary adenosine administration on preventing no-reflow phenomenon during rotational atherectomy of complex coronary artery lesions

P1-17 Effects of intracoronary adenosine administration on preventing no-reflow phenomenon during rotational atherectomy of complex coronary artery lesions

Angiographic analysis of immediate and long‐term results of PTCR vs. PTCA in complex lesions (COBRA study)

We conducted a prospective, randomized trial to compare immediate and long-term effects of percutaneous transluminal coronary angioplasty (PTCA) and high-frequency rotational atherectomy (PTCR) in patients with angiographically predefined complex coronary artery lesions (AHA type B2 and C). The relation of lesion characteristics to procedural results is reported in this angiographic analysis. Patients were randomly assigned to balloon angioplasty (n = 250 patients) or rotational atherectomy (n = 252 patients). Quantitative coronary angiography could be performed in 447 patients to evaluate immediate results and in 293 patients with a 6-month angiographic follow-up. Procedural success was comparable in the PTCR and in the PTCA group (80% vs. 76%, P = 0.260). The need for stent implantation due to a residual stenosis >50% or a bail-out situation was significantly higher in the PTCA group (9.7% vs. 2.0%, P = 0.001). In both treatment groups, diameter stenosis was effectively reduced and MLD increased. The acute gain did not differ between the two groups. At 6-month control, the restenosis rate was comparable in the PTCR and in the PTCA group (37% vs. 35%, P = 0.658), whereas diameter stenosis was significantly more severe in the PTCR group than in the PTCA group (52% vs. 46%, P = 0.039) and, correspondingly, the MLD was significantly smaller in the PTCR group (1.29 mm vs. 1.44 mm, P = 0.031). Late loss was about the same in both groups, however, net gain and net gain index were significantly higher in the PTCA group (0.82 mm vs. 0.64 mm, P = 0.008; and 31% vs. 24%, P = 0.009). Analysis of procedural results for various lesion characteristics revealed no significant difference between treatment groups. In this randomized trial, complex coronary artery lesions were treated with comparable results for angiographic and procedural success and the restenosis rate by both, PTCA and PTCR. Late loss, however, was significantly higher and net gain significantly smaller after PTCR. Stents, although infrequently used, had a relevant impact on immediate PTCA results but not on late results. Cathet Cardiovasc Intervent 2001;53:359-367.

Update on Percutaneous Intervention in Left Main Artery Stenosis

Advances in percutaneous intervention make it possible to expand the use of angioplasty to multiple and complex coronary artery lesions. Unfortunately, unprotected left main coronary artery (LMCA) stenosis has been regarded as a contraindication of percutaneous intervention because of its potential risk of early cardiac death and poor late clinical outcomes. However, LMCA stenosis is an attractive target for percutaneous intervention because of its larger caliber, short lesion length, and lack of tortuosity. Recently, stenting of unprotected LMCA stenoses has been reported with promising results in carefully selected patients. It now can be considered as a therapeutic option of unprotected LMCA stenoses in selected centers. This article summarizes the current status, technical considerations, and future directions of percutaneous intervention in the treatment of unprotected LMCA stenoses.

A new approach for the quantification of complex lesion morphology: The gradient field transform; Basic principles and validation results

Objectives. This report describes the basic principles and the results from clinical evaluation studies of a new algorithm that has been designed specifically for the quantification of complex coronary lesions.Background. Currently used edge detection algorithms in quantitative coronary arteriography, such as the minimum cost algorithm, are limited in the precise quantification of complex coronary lesions characterized by abruptly changing shapes of the obstruction.Methods. The new algorithm, the gradient field transform, is not limited in its search directions and incorporates the directional information of the arterial boundaries. To evaluate its accuracy and precision, 11 tubular phantoms (sizes 0.6 to 5.0 mm), were analyzed. Second, angiographic images of 12 copper phantoms with U-shaped obstructions were analyzed by both the gradient field transform and the minimum cost algorithm. Third, 25 coronary artery segments with irregularly shaped obstructions were selected from 19 routinely acquired angiograms.Results. The plexiglass phantom study demonstrated an accuracy and precision of −0.004 and 0.114 mm, respectively. The U-shaped copper phantoms showed that the gradient field transform performed very well for short, severe obstructions, whereas the minimum cost algorithm severely overestimated the minimal lumen diameter. From the coronary angiograms, the intraobserver variability in the minimal lumen diameter was found to be 0.14 mm for the gradient field transform and 0.20 mm for the minimum cost algorithm.Conclusions. The new gradient field transform eliminates the limitations of the currently used edge detection algorithms in quantitative coronary arteriography and is therefore particularly suitable for the quantification of complex coronary artery lesions.